1. Combine chicken broth, vinegar, oregano, olive oil, sugar, garlic, salt and pepper in a small bowl. Set aside all but 2 tablespoons of the dressing. Preheat grill or broiler.2. Brush chicken breasts with the 2 tablespoons of dressing. Place on grill rack or broiler pan coated with cooking spray. Cook for 5 minutes on a side or until chicken is done. Cut into slices ¼ inch thick. 3. Combine lettuce, cucumbers, tomatoes, and onion in a large bowl and toss with reserved salad dressing. Top salad with chicken, olives and feta cheese. Serve immediately.